As Internet traffic continues to dramatically increase, today's communication and data networks face many challenges to support and manage the vast amounts of Internet data. Specifically, modern optical networks are constantly faced with demands to increase bandwidth for a single-wavelength, implement flexible connection requests, and provide on-the-fly support for new applications, such as network virtualization. One method to improve modern optical networks has been the advancement in optical coherent communication technologies that create software-defined cognitive optical networks (CONs). CONs can support reprogramming of hardware transmission logic and new network applications (e.g. adaptive bandwidth services) by using intelligent software, such as digital signal processing (DSP) software in the optical transport plane and generalized multi-protocol label switching (GMPLS) in the optical control plane, and flexible hardware, such as bandwidth-variable reconfigurable optical add/drop multiplexers (ROADMs) and optical orthogonal frequency-division multiplexers (OOFDMs).
Additionally, with a surge of data center applications like cloud computing and pressure to reduce capital expenditure (CAPEX) and operating expenditure (OPEX) for service providers, the trend in the telecommunication industry has been to integrate packet transport platforms with optical transport platforms. Some examples of integrating transport platforms with optical transport platforms include Ethernet over optical transport network (OTN), Internet Protocol (IP) over wavelength division multiplexing (WDM), and GMPLS unified control plane technologies. However, integrating transport platforms with optical transport platforms creates complex networks that are often difficult to manage, inflexible, and may not be service extensible. For instance, managing a packet-optical transport network may involve using highly adaptive service provisioning. The transport functions may need to not only provide bandwidth-on-demand (BoD) between a pair of source and destination nodes to accommodate dynamic packet flows efficiently, but also provide reliable circuit among a set of nodes with minimum delay and different bandwidth granularities to form an application-specific virtual network (e.g. virtual network service).
The latest effort in managing an integrated packet-optical transport network has been the development of Software-Defined Networking (SDN), path computation element (PCE) protocols, and Open Flow (OF) protocols. Fundamentally, SDN decouples the control and forward planes within a network and uses a centralized controller to manage the control plane functions. The combination of SDN and OF can create highly scalable Ethernet switch networks by virtualizing the layer 2 (L2) and layer 3 (L3) data center network. The SDN virtualization may also virtualize L2/L3/layer 4 (L4) switches, routers, and firewalls in terms of sharing IP/media access control (MAC) addresses and improve forwarding bandwidth among a variety of higher layer clients. Unfortunately, the existing L2 and L3 virtualization approaches are unable to guarantee deterministic latency, jitter, and resilience for a variety of circuit services, as L2 and L3 switches intrinsically have relative poor bandwidth isolation capability. Furthermore, current SDN development focuses on virtualization of packet networks and does not provide for virtualization of WDM transport networks.